/Engine/Plugins/Animation/LiveLink/Source/LiveLink/Public/LiveLinkClient.h
Whether or not the client has a subject with this name enabled Only 1 subject with the same name can be enabled. At the start of the frame, a snapshot of the enabled subjects will be made. That snapshot dictate which subject will be used for the duration of that frame.
virtual bool IsSubjectEnabled ( [FLiveLinkSubjectName](API\Runtime\LiveLinkInterface\FLiveLinkSubjectName) SubjectName ) const